1. Field
One embodiment of the present invention relates to information recording and reproducing methods, and information recording and reproducing apparatuses, which are suited to record and reproduce a digital stream signal (MPEG-TS) and the like used in satellite digital TV broadcasting, terrestrial digital TV broadcasting, and the like.
More particularly, the invention relates to recording and reproducing methods, and recording and reproducing apparatuses of a digital stream signal compatible to an MPEG-TS including video data encoded by MPEG-4 AVC (or H.264).
2. Description of the Related Art
In recent years, TV broadcasting has entered the era of digital broadcasting having Hi-Vision programs (programs of high-definition AV information) as principal broadcasting content. The current BS digital broadcasting (and forthcoming terrestrial digital broadcasting) adopts an MPEG2 transport stream (to be abbreviated as MPEG-TS hereinafter as needed). In the field of digital broadcasting using moving pictures, the MPEG-TS will be used as a standard format in the future. Upon the initiation of such digital TV broadcasting, market needs for a streamer that can directly record digital TV broadcasting content are increasing. As an example of such streamer, one disclosed in JP-A 2004-295947 (KOKAI) is known.
This application proposes that a digital stream signal compatible to the MPEG-TS is handled as a stream object. Also, this application proposes that attribute information associated with the stream object is generated as management information and is recorded upon recording of the stream object, so as to realize high random accessibility upon reproducing the stream object. Furthermore, this application takes, as a practical example of a digital stream signal to be recorded, ARIB (Association of Radio Industries and Businesses) as the digital broadcasting standard in Japan. As other digital broadcasting standards, DVB (Digital Video Broadcasting) in Europe and ATSC (Advanced Television Systems Committee) in U.S.A. are known. These broadcasting standards adopt a digital stream signal compatible to the MPEG-TS.
The MPEG-TS is data obtained by appending synchronization data and the like to moving picture data, audio data, and the like, and multiplexing them, and moving picture and audio data to be multiplexed in the MPEG-TS can use some encoding formats. The practical examples of the digital stream signal adopt MPEG-2 Video as the moving picture encoding format. When the streamer records the MPEG-TS multiplexed with MPEG-2 Video data, it needs to demultiplex the MPEG-2 Video data from the MPEG-TS, and acquire attribute information by cognizing (or analyzing) the MPEG-2 Video structure so as to generate the attribute information of the stream object as management information.
On the other hand, in recent years, H.264/MPEG4-AVC (to be abbreviated as H.264 hereinafter as needed) has received a lot of attention as a novel moving picture encoding format. H.264 can attain moving picture encoding at a compression ratio higher than MPEG-2 Video, and draws attention as a moving picture encoding scheme in digital broadcasting and that used upon saving in the streamer. However, as is known, the H.264 structure is harder to cognize than MPEG-2 Video. Therefore, upon recording the MPEG-TS multiplexed with H.264 data by the streamer, it is difficult for the streamer to obtain attribute information by cognizing the deep part of the H.264 structure.